The erosion that exceeds the normal geologic erosion and becomes destructive. It occurs when people disturb the soil or the natural vegetation by cutting forests, overgrazing, ploughing hillsides, recreational activity (e.g., ATV vehicle uses), indiscriminate (arbitrary) burning, or construction of roads and buildings.

Process whereby soil becomes acid (pH < 7) because acid parent material is present or in regions with high rainfall, where soil leaching occurs. Acidification can be accelerated by human activities (use of fertilisers, deposition of industrial and vehicular pollutants).